The leotard and tights fetish seems popular in Japan. I can demonstrate with some pictures I've collected over the years. I'll start with some where the guy is trying to look femme and go on to some more androgynous ones. The first are from a long dead website called BodyDressingYuka.

Yuka in his aerobics class:

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his dance lesson
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and doing rhythmic gymnastics.
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In swimsuits
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and as a race queen.
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Here's another guy, Asuka, who's into shibari:
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